Recent advancements in the Messinian stratigraphy of Italy and their Mediterranean-scale implications

A careful revisitation of Late Miocene successions of Italian basins carried out in the last ten years provided asignificant advancement in the understanding of Messinian salinity crisis (MSC) events. New facies models for both primary andresedimented evaporites and an integrated stratigraphic approach allowed to trace key surfaces across the depositional settings ofindividual basins and to correlate the Messinian record of basins developed in different geodynamic settings. This results in a highresolutionand dynamic stratigraphic scenario which accounts for the effects of Mediterranean-scale and local forcing factors andallows to assess important and still obscure items, like the nature of deep basinal Lower Evaporites and the meaning of the Lago-Mareevent. As for the Lower Evaporites, this study suggests that they actually consist of both primary and resedimented facies fully separatedin both time and space. Resedimented evaporite units have a clear chronostratigraphic value and were deposited in basinal settingsduring the MSC acme, following an important tectonic pulse; these deposits, which are associated with halite in Sicily and Calabriabasins, fully postdate the primary evaporites (massive selenite gypsum) formed only in small, shallow and semiclosed basin in the firstphase of MSC. The Lago-Mare event is characterized by the progressive dilution of surface waters after the MSC peak; the highresolutionstratigraphy obtained for the Late Messinian interval suggests that this important change in basin hydrology and precipitationregime, possibly resulting from a complex interplay between tectonic and climatic factors, occurred in all the basins at around 5.42 Ma,thus defining a much more homogeneous scenario than previously thought for this event.